How does planet invasion work?

I feel so confused because I see the planet defense to something like 500. My fleet brought more than a thousand but seems to deploy only 650.

Then if I am unable to kill all the defense in a turn it gets fully refilled the following turn and so on and so on. Does it come from the enemy global manpower ? 

But it still doesn't make sense because its taking me 10s of turns as I have to deplete all the local population ( as the ai is using 'conscription' battle tactic from time to time).

Also if I equip Titanium Slugs on my ships( which deplete enemy defense ) and wait 2-3 turns to be sure to be able to kill everything in a single invasion turn, this will only take ~2-3 turns instead of 20-25 on heavy populated system...

I feel like the current implementation lacks a lot of UI information and is not well balanced. Here is what I figured it out:

• I can bring like 5,000 invasion force with my ships but only ~600 will be used per turn. My remaining pool is somewhere in the system and there is nowhere to see that pool value. It's not staying in the ships because they all went to 0% crew immediately when I started the invasion and I can move the ships to different system and my local pool will stay in the system I'm invading ( waiting in orbit?)
• having the choice to invade without Titanium Slugs and take 20-30 turns on heavy populated system or use the Titanium Slugs for 2 turns to be able to get the system with a single invasion turn feels like it's not yet balanced! And nothing is really explained in game.
• how can the invaded system be able to refill its local manpower when my ships are blockading the system and doing ground invasion every turn? It feels like an unending invasion and I still think the opponent will always fully refill the local manpower as he is getting enough manpower per turn to easily refill 500 troops.
• All the nice extras features like upgrading your troops and making tanks and planes are useless in comparison of simply sieging with Titanium Slugs for a couple of turns. This only requires ~600 of troops in total and doesn't rise your militarist party like crazy !

If anybody as an explanation of the invasion mechanism I'd glad to hear it.

When you invade an enemy system, all your troops land at the same time. Sadly, there is no way to see their total manpower after that. 

You can increase deployment limit through technologies up to 1200, and i belive some Hero skills can increase it further - up to 1350. 

Not sure if special siege modules are OP. In most cases you can take a system by going straight for ground invasion in 2 or 3 turns. Losing manpower is not a problem late game, and you don't have to sacrifice firepower/defense on your fleet. Siege modules are really useful for 3000+ manpower systems however.

AFAIK systems that are being invaded do not refill their manpower. What you're seeing is likely the result of conscription tactic. If you can't kill all of their deployed troops they can bring more troops every turn as long as they have enough population. Also note that enemy fleets will contribute their manpower to the system defenses.

I absolutely agree with what the OP has written here. I stumbled over the exact same issues. I'm never too sure about the absolute manpower number before and after battles, too. In my last game it was 700. 

I've seen steady improvements of ground battles since I have the game and am looking forward to all of these issues getting adressed. 

Starmender wrote:

When you invade an enemy system, all your troops land at the same time. Sadly, there is no way to see their total manpower after that. 

This is a serious problem, and it's not explained anywhere! Nor is it explained what happens to these troops after the invasion - I think they're quickly suctioned back up into ships, but I can't tell if that's regular manpower replenishment or not.

Hi !

These are elements we want to adress with some rework of the Ground Battle GUI :) (Seeing total manpower engaged, limits, how limits are raised etc)

Cheers,

Starmender wrote:

What you're seeing is likely the result of conscription tactic. 

Exactly.  This explains why when you get them down to 10, then you attack again them next turn and magically they have 20. Take a look at the the final screen and you will see that the enemy used conscription.

Siege modules are effective but they seem to be missing something. If we imagine that during this process an extensive orbital bombardment is occuring, then the collateral damage is surprisingly low. There's just a blockade penalty, nothing gets destroyed. The only cost to an orbital siege is time. Surely that's the wrong way round?